Heavy oil feed pump



March 28, 1961 F. w. PLEUGER Erm. 2,976,812

HEAVY OIL FEED PUMP 2 Sheets-Sheet 1 Filed Sept. 9, 1958 March 28, 1961F. w. PLEUGER ErAL 2,976,812

HEAVY OIL FEED PUMP 2 Sheets-Sheet 2 l LII Filed Sept. 9, 1958 nitd SQCSPatent e HEAVY OIL FEED PUMP Friedrich Wilhelm Pleuger, Juthornstrasse80, and Heinz Ghring, Hamburg-Wandsbek, Germany; said Ghring assignor tosaid Pleuger Filed Sept. 9, 1958, Ser. No. 759,927

Claims priority, application Germany Sept. 10, 1957 13 Claims. (Cl.10S-179) The invention relates to a heavy oil feed pump with a hollowpiston slidingly mounted on the outer surface of a hollow cylinder,which piston includes a knife-edgeshaped end provided with a ap valvewhich is linked to a piston rod centrally guided in the hollow cylinderso that the piston rod can be moved by a limited amount with respect tothe hollow piston and so that the ilap valve |alternately closes andopens on any reversal of piston movement.

The present invention has the purpose of improving heavy oil pumps ofthe kind mentioned and of so constructing them that an improvedconnection is achieved between the ap valve and the hollow piston,whereby wear is reduced and the durability of heavy oil pumps increased.Furthermore, by the invention, a lesser loading of the actuating memberprovided between the piston rod and the flap valve is achieved.

To solve the problems mentioned, in accordance with the invention, it isproposed to connect the flap valve with a lost motion connection to itsactuating rod operated by the piston rod and to mount it eccentricallywith respect to the hollow piston axis, so that, after a partial closingby the actuating rod, it is urged into the fully closed position by thehydrostatic pressure of the oil contained in the hollow piston. A boltand longitudinal slot connection between the piston rod and an-intermediate lever pivotally connected with a pivot arm on the flapvalve preferably provides for the necessary lost motion between the apvalve and the piston rod.

According to a further feature of the invention, the flap valve, whosepivot is preferably arranged outside the sealing plane of the valve, isconstructed as a circular valve plate, which co-operates with a valveseating ring inserted in the hollow piston and includes a ring providedwith sealing surfaces, which ring is axially shiftably mounted insealing fashion on an inner guide part of the ap valve. To support theflap valve in the closed position, a counter-bearing is preferablyarranged in the hollow piston beneath the flap valve.

Further details and features ofthe invention will appear from thefollowing description and the accompanying drawings in which anembodiment of the invention is illustrated.

In the drawings:

Fig. 1 shows the whole of the heavy oil pump accord- -ing to theinvention during the upward and supply stroke;

Fig. 2 shows the lower part of the pump illustrated in Fig. l on anenlarged scale; Y

Fig. 3 shows the lower part of the heavy oil pump according to theinvention during its downward stroke;

Fig. 4 shows a broken-away sectional illustration of a furtherembodiment of the heavy oil supply pump accord- `ing to the invention,which can be releasably inserted in a rising pipe as an inserted pump.

In the various figures, the same or corresponding parts are providedwith the same references.

The pump housing constructed essentially as a hollow 2,976,812 PatentedMar. 28, 196.1

cylinder 1 is screwed into a connecting member 2, by means of which itcan be screwed into a rising pipe in the usual way. The threadingbetween the rising pipe and the connecting member 2 consists of ahelical thread 4. The screw connection 5 between the hollow cylinder 1and the connecting member 2 is sealed by means of a sealing ring 6.

A hollow piston 7 is slidingly mounted on the hollow cylinder 1. Thehollow piston 7 carries on its upper end, as a seal, a stop bushing Swhich can be drawn up by menas of a screw-threaded ring 9. In order tominimize friction between the hollow cylinder 1 and the hollow piston 7,a sand protecting ring 51 is inserted at the lower end of the hollowcylinder 1. At the lower end of the hollow piston 7, across head 10 isarranged which has a guide bushing 11 in its middle part, in which thelower end of a piston rod 12 is guided. The piston rod 12 extendsaxially through the hollow cylinder 1 land is provided at its upper endwith a connecting member 13 by which it can be connected to a pumpactuating rod of normal construction. A further guide for the piston rod12 is the abutment member 14, which is rigidly inserted in the hollowcylinder 1 and is surrounded by a bearing bushing 15.

In the hollow piston 7 in the vicinity of its forward knife-edge-likeend, a flap valve 16 made of several parts is provided, including aninner guide member 41 and a valve ring 42. The valve ring 42 is mountedin its axial direction so as to be limited as regards movement relativeto the inner guide part 41 and is sealed by a sealing ring 43. On theforward side of the inner guide part 41, a counter-bearing plate 44 issecured by screws 45. This plate has a projecting peripheral part 46 forlimiting the axial movement of the valve ring 42. An elastic ring 4'7inserted between the valve ring 42 and the peripheral part of thecounter-bearing plate 44 cushions the relative movements between thevalve ring 42 and the inner guide part 41. The flap valve 16 ispivotally mounted about a bolt 17 inserted in the hollow piston 7. Thesealing between the flap valve 16 and the hollow piston 7 is eiected byco-operation between the valve ring 42 and a seating ring 48 inserted inthe hollow piston 7, which, in the same way as the correspondingycounter surface of the valve ring 42, is chamfered in conical shape. l

A pivot arm 18 is provided for moving the valve mem ber 16 and is linkedby means of a bolt 20 to a rigid intermediate lever 22, which in turn isconnected pivotally with the piston rod head 27. The piston rod head Z7is screwed to the free end of the piston rod 12 by means of a screwthread 28 and is secured by means of a bolt 29.

An elongated slot 49 is located in the piston rod head 27 in which theconnection bolt 30 of the intermediate lever 22 is guided.

For inserting the flap valve and the actuating rod, the hollow piston 7is made in several parts and consists, apart from its main section, oftwo short end sections 7' and 7, which are connected together by meansof screw thread connections. Between the hollow piston sections 7 and7", the valve seating ring 48 is inserted. Further, in the lowermosthollow piston section 7", a counter-bearing bolt 50 is located, on whichthe middle part of the flap valve 16 can be supported in the closedposition illustrated in Fig. l.

An annular valve seat 3l is inserted above the cross head 10 in thehollow cylinder 1. This valve seat 31 co-operates with aconically-shaped valve body 32 which is mounted with a central bore onthe piston rod 12. In order to achieve a satisfactory sealing with thevalve body 32 with respect to the piston rod 12, a stop bushing isarranged inside the valve body 32, which consists of the sealing lips 33and the screw-threaded nipple 34.

By means of the upper abutment member 14, which co-operates with theprojection 40 on the piston rod, the downward movement of the heavy oilpump is limited. The limitation of the upward movement of the heavy oilpump is effected with the aid of the piston rod head 27, which abuts theguide bushing 11 of the cross head 10.

The heavy oil pump according to the invention operates as follows:

The pump is installed in the oil supply line in the vertical positionand the connecting member 2 is screwed with its helical thread on to thelower` end of a rising pipe. The connecting member 13 of the piston rodis connected with a powered upwardly and downwardly movable actuatingrod. It will be understood that the pump does not need to operate withthe maximum stroke determined by the upper and lower stroke limits, butthat the piston rod can be moved to-and-fro by its drive over a smallerstroke.

In the downward movement of the piston rod 12, the pump parts assume thepositions illustrated in Fig. 3. The piston rod head 27 is lowered fromthe cross head 10 and has swung the flap valve 16 via the intermediatelever 22 so that it is in the position shown in Fig. 3. In thisposition, the link bolt 30 between the intermediate lever 22 and thepiston rod head 27 lies at the upper edge of the elongated slot 49. Bythe transmission of force from the piston rod 12 via the intermediatelever 22 and the valve ap bolt 17 and also by its weight, the hollowpiston 7 is moved downwardly until its sharpened front surface 3S isforced into the viscous heavy oil to be supplied.

As soon as the piston rod has reached its lowest point, its movementreverses and it begins to move upwardly again. The initial movement ofthe piston rod is elected rstly without carrying up the hollow piston 7,since the piston rod head 27 is not against the cross head 10.

In this initial movement of the piston rod, the flap valve 16 moves fromthe open position illustrated in Fig. 3 in the direction towards theclosed position illustrated in Figs. l and 2. By reason of the long slotand bolt connection 30, 49 provided between the piston rod head 27 andthe intermediate lever 22 and the specially selected dimensions, theiiap valve 16 cannot be completely closed by the relative movementbetween the piston rod and the hollow piston 7, but a slight clearanceis initially maintained between the valve ring 42 and the seating ring48. Since the pivot axis 17 for the flap valve 16 is arrangedeccentrically with respect to the hollow piston 7, the amount of heavyoil closed off above the iiap valve operates by its hydrostatic pressureso that it eiects complete closure of the flap valve. In this secondcompleted closure movement of the valve, the valve ring 42 moves in theaxial direction with respect to the inner guide member 41 until there istight engagement of the sealing surfaces of the two rings 42 and 48. Inthis completely closed position, the middle `part of the ap valve member16 rests upon the counter bearing bolt t). Y

By the two part closure movement achieved in accordance with theinvention, of which the lirst is effected exclusively by the piston rodand the second exclusively by the hydrostatic pressure, there is given,without using corrosion-sensitive spring elements, a very easy operationof the valve and sharp mechanical strokes on the seating surfaces of thevalve are safely excluded in operation. The resulting extension of thelife of the Ypump is obvious. It may be mentioned that, between theinner guide part 41, 44 and the valve ring 42 of the flap valve 16, aring 47 consisting of elastic material can be provided, which provides acushioning additional to that already achieved due to the viscosity ofthe oil.

After the flap valve 16 has closed and the piston rod head 27 hascontacted the cross head 10, the whole hollow piston together with theamount of heavy oil enclosed above the valve plate 16 moves upwardlywith respect to the stationary hollow cylinder 1. In this supplymovement, the heavy oil at the cross head 10 is forced through thecentral valve seat 31. The valve cone 32 is raised against thepressureof the oil column but prevents return of the oil on reversal of themovement of the piston rod. Above the valve cone 32, the heavy oil canbe raised further by the projection 14 illustrated in section, in orderto be advanced with the piston rod 13 and the enclosed pump rod via therising pipe (not shown) but which is coupled to the member 2 asdescribed.

The embodiment of Fig. 4 is an insert pump which, in contrast to theusual deep well pumps, is not insertable and removable by means of therising pipe, but exclusively by the pump rod and hence involves aconsiderfable saving in time and cost. Whereas in the embodiment ofFigs. l to 3 the pump housing 1 constructed as a hollow cylinder isscrewed into the rising pipe by an intermediate member 2, in theembodiment according to Fig. 4, a rapidly releasable connection betweenthe rising pipe and the pump housing 1 is provided.

For connecting the pump housing 1 and the rising pipe 52, a hardenedsteel ring 53, a spread connecting sleeve 54 provided at severalpositions on its periphery with longitudinal slots and a hardened steelring 55 are provided. The steel ring 55 and the expanded connectingsleeve S4 are secured to a housing part 56 which, instead of theabutment member 14 ofthe construction according to Figs. l to 3,undertakes guiding of the piston rod 12 and is connected with the hollowcylinder 1 by means of a connecting sleeve 57. As can be seen from Fig.4, the housing part 56 consists of two cylindrical sections which arereceived between the ring 53 and the sleeve 54. The steel ring 5S issecured in the region of a connesting sleeve 58 by screwing between twosections of the rising pipe 52. The outer diameter of the ring 53 isgreater than the inner diameter of the ring S5 and smaller than theinner diameter of the rising pipe 52, so that on inserting the pump 1nthe rising pipe the ring 53 can rest on the ring 5S in order to limitdownward movement of the hollow cylinder 1. The slotted connectingsleeve 54 is so dimensioned that its minimum outer diameter is smallerthan the inner diameter of the ring 55, whereas its maximum outerdiameter, that is its outer diameter in its expanded state, is greaterthan the inner diameter of the ring 55 and somewhat smaller than theinner diameter of rising pipe 52. In this way, the connecting sleeveforms Yan abutment which limits upward movement of the hollow cylinder1.

The insertion of the pump in the rising pipe 52 is effected by insertingthe pump from above into the rising pipe until the initially stressedparts of the connecting sleeve v54 are spread or expanded outwardlybehind the ring 55 and the ring 53 comes to rest upon the upper edge ofthe ring 55.

In order to ensure a tight seating of the pump in the rising pipe, theopposite inclined surfaces between the 'rings 53 and 55 and between thesleeve 54 and ring 55 are made inclined. The inclination between thefront surface of the sleeve S4 and the ring 55 preferably amounts toabout 30, so that on applying a tensile force to the housing part 56which exceeds the normal actuating force of the pump, the snapconnection between the elements 53, 54 and 55 can again be released.

The operation of the pumping process is the same as 'in the pumpembodiment described previously in connection with Figs. l to 3. Asshown in Pig. 4, a screwable rod coupling 59 is provided as theconnection between the piston rod 12 and the pump actuating rod. Inorder to release this screwable rod coupling 59, projections 60 of a dogcoupling are provided on the downwardly-directed front face of thecoupling 59, which can co-operate with upwardly-directed projections 61on the housing part 56. If the pump rod and hence the piston rod aremoved downwardly, the projections 60 and 61 of the dog cou-` phng areengaged together, so that then the pump rod can be rotated relatively tothe piston rod 12 to release the coupling.. The projections 60 and 61form further one lower llimiting abutment for the pump rod and at thesame time determine the lowest point of the hollow piston 7, 1n order toprevent the latter from shifting too far with respect to the hollowcylinder 1.

What we claim is: i

1. In pumping apparatus for an oil well the combination of a riser, apiston rod, a hollow cylinder secured to the riser, a hollow pistonslidably mounted on the outer surface of the cylinder, a cross head forthe piston rod secured to the inner wall of the hollow piston, saidpiston rod being mounted `to project through and slide with respect tothe cross head, an enlargement secured to the piston rod below the crosshead, which enlargement is adapted to be moved away from the cross headon the downward stroke of the piston rod and to be returned to engagethe cross head on the upward stroke of the piston rod, whereby thehollow piston is supported by the piston rod, a ap valve pivoted in saidhollow piston below said cross head upon a transverse axis at one sideof the longitudinal axis of the hollow piston, operating linkage meansbetween the piston rod and the flap valve, said linkage means includinga lost motion coupling and said ap valve having an axially movable valvering, and a seating ring carried by the inner wall of the hollow pistonin position to cooperate with said valve ring, the flap valve beingadapted to be moved by the linkage means to elect partial closing of thehollow piston and said valve ring being adapted to be moved by thehydrostatic pressure of the oil contained in the hollow piston to seatupon said cooperating seating ring and thereby complete the closure ofthe hollow piston during upward movement thereof.

2. In pumping apparatus for an oil well the combination of a riser, apiston rod, a hollow cylinder, a snap connection securing the hollowcylinder to the riser, the holding force of which snap connectionexceeds the piston rod forces, a hollow piston slidably mounted on theouter surface of the hollow cylinder, a cross head for the piston rodsecured to the inner wall of the hollow piston, said piston rod beingmounted to project through and slide with respect to the cross head, anenlargement secured to the piston rod below the cross head, whichenlargement is adapted to be moved away from the cross head on thedownward stroke of the piston rod and to be returned to engage the crosshead on the upward stroke of the piston rod, whereby the hollow pistonis supported by the piston rod, a ap valve pivoted in said hollow pistonbelow said cross head upon a transverse axis at one side of thelongitudinal axis of the hollow piston, operating linkage means betweenthe piston rod and the flap valve, said linkage means including a lostmotion coupling and said ap valve having an axially movable valve ring,and a seating ring carried by the inner wall of the piston in positionto cooperate with said valve ring, the ap valve being adapted to bemoved by the linkage means to effect partial closing of the hollowpiston and said valve ring being adapted to be moved by the hydrostaticpressure of the oil contained in the hollow piston to seat upon saidseating ring and thereby complete the closure of the hollow pistonduring upward movement thereof.

3. Pumping apparatus according to claim 2 wherein the snap connectionincludes a tirst ring rigidly secured in said riser, a second ringdisposed on said hollow cylinder and an expansible sleeve spaced fromsaid second ring and also disposed on said hollow cylinder, said firstring being arranged to occupy the space between said second ring andsaid expansible sleeve and being adapted to cooperate therewith.

4. In pumping apparatus for an oil well the combination of a riser, apiston rod, a hollow cylinder, a snap connection securing the hollowcylinder to the riser, the holding force of which snap connectionexceeds the piston rod forces, a hollow piston slidably mountedY on theouter surface of the hollow cylinder, a cross head for, the piston rodsecured to the inner wall of the hollow piston, said piston rod beingmounted to project through and slide with respect to the cross head, anenlargement secured to the piston rod below the cross head, whichenlargement is adapted to be moved away from the cross head on thedownward stroke of the piston rod and to be returned to engage the crosshead on the upward stroke of the piston rod, whereby the hollow pistonis supported by the piston rod, a circular valve plate in said hollowpiston below said cross head, said valve plate being pivoted in saidhollow piston upon a transverse axis at one side ofthe longitudinal axisof the hollow piston, operating linkage means between the piston rod andthe circular valve plate, said linkage means including a lost motioncoupling, a seating ring carried by the inner wall of the hollow piston,said valve plate including an inner guide surface, a valve ring which isaxially slidable on said inner guide surface, said valve ring havingsealing surfaces adapted to cooperate with the seating ring on the wallof the hollow piston, said circular valve plate with its sliding valvering being adapted to be moved by the linkage means to effect partialclosing of the hollow piston and said sliding valve ring being adaptedto be moved by the hydrostatic pressure of the oil contained in thehollow piston to seat upon said cooperating seating ring and therebycomplete the closure of the hollow piston during upward movementthereof.

5. Pumping apparatus according to claim 4 wherein the snap connectionincludes a tirst ring rigidly secured in said riser, a second ringdisposed on said hollow cylinder and an expansible sleeve spaced fromsaid second ring and also disposed on said hollow cylinder, said firstring being arranged to occupy the space between said second ring andsaid expansible sleeve and being adapted to cooperate therewith.

6. Pumping apparatus according to claim 1 wherein the linkage meansincludes a pivot arm on the flap valve and a lever coupling said armwith the piston rod, and wherein the lost motion is provided for by aslot and bolt connection at one end of the lever.

7. Pumping apparatus according to claim 1 wherein the ap valve pivot isarranged outside the sealing plane of the valve.

8. Pumping apparatus according to cl-aim l wherein the valve seatingring is disposed in the hollow piston in a plane which is perpendicularto the longitudinal axis of the piston and wherein the ap valve isformed as a circular valve plate.

9. Pumping appartus `according to claim 8 wherein the seating ring andthe valve ring are provided with conically inclined cooperating seatingsurfaces.

10. In pumping apparatus for an oil well the combination of a riser, apiston rod, a hollow cylinder secured to the riser, a hollow pistonslidably mounted on the outer surface of the cylinder, a cross head forthe piston rod secured to the inner wall of the hollow piston, saidpiston rod being mounted to project through and slide with respect tothe cross head, an enlargement secured to the piston rod below the crosshead, which enlargement is adapted to be moved away from the cross headon the downward stroke of the piston rod and to be returned to engagethe cross head on the upward stroke of the piston rod, whereby thehollow piston is supported by the piston rod, a circular valve platepivoted in said hollow piston below said cross head upon a transverseaxis at one side of the longitudinal axis of the hollow piston, a valveseating ring disposed in the hollow piston in a plane which isperpedicular to the longitudinal axis of the piston, operating linkagemeans between the piston rod andthe valve plate, said linkage meansincluding a lost motion coupling and said valve plate including an innerguide member and a sealing ring mounted for axial, sliding movement onthe guide member, and means 'limit- 7 ing said movement, whereby, aftera partial closing by said linkage means, the valve ring is forced into afully closed position by the hydrostatic pressure of the oil containedin the hollow piston. i

11. Pumping apparatus according to claim 10 wherein a. counter-hearingis arranged in the hollow piston beneath the valve plate on which thesaid plate will be supported when the plate is in closed position.

12. Pumping apparatus according to claim 10 wherein an elastic ring isinterposed between the guide member and the means for limiting saidsliding movement whereby to cushion the sliding movement of the valvering.

13. Pumping apparatus according to claim 1 wherein said hollow cylindercarries a sand protecting ring at S its lower end adapted to seal thesliding surfaces betwce said hollow cylinder and said hollow piston. Y IY References Cited in the file of this patent vUNITED STATES PATENTS90,157 Y Devirs et a1. Mag/18, 1869 282,973 Everitt Aug. 14, 1883436,548 Smith Sept. 16, 1890 602,869V ONeil T Apr. 26, 1898 '11,871,577Babin Aug. 16, 1932 2,519,142 Lehr Allg. 15, 1950 V2,825,288 PleugerMar. 4, 1958 e v FOREIGN PATENTS 23,271 Great Britain of 1894

